I have a variety of clients who over the last couple of days now have 5 all in one PC's from different vendors who can't login. When you get to the click on your user screen it just blanks out and flashes and then returns.

Safe mode won't let you login in at all, it just gets stuck. The interesting thing is that all 5 are AMD powered running Win 7 Home Premium and this has occured over the last couple of days.

Anyone else seen this? At this stage I haven't found a fix except for possibly reinstalling Windows.....